Electrolytic condenser



R D. MERSHON. ELECTROLYTIC CONDENSER.

APPLICATION FILED NOV-3,1919

Patented N 0v. 28, 1922..

2 SHEETSSHEET 1- Fig.1

,R. D. MERSHON.

ELECTROLYTIC CONDENSER.

APPLICATION FILED NOV. 3, 1919.

1,437, 1 89. Patented Nov. 28, 1922.

2 SHEETS-SHEET 2.

IH if H1 1! l/VVENTOR A TTORNEYS.

Patented Nov. 28, 1922.

UNITED STATES RALPH D. MERSHOI\T, OF NEW YORK, N. Y.

ELECTROLYTIC CONDENSER.

Application filed November 3, 1919.

To all whom it mgficoncern:

Be it known that I, RALPH D. MERsHoN, being a citizen of the United States, residing at New York, county and State of New York, have invented certain new and useful Improvements in Electrolytic Condensers, of

which the following is a full, clear, and exact description.

This invention relates to electrolytic condensers and its chief object, briefly stated, is to improve condensers of this type by providing shorter paths, through the electrolyte, for the current from the outer surfaces of the plates or electrodes at the ends of the series. To this and other ends the invention consists in the novel features and combinations of elements hereinafter described.

Referring to the accompanying drawings:

Fig. 1 is a diagrammatic plan view of the ordinary electrolytic condenser, the outer tank or containing vessel being shown in horizontal section.

Fig. 2 is a diagrammatic plan view of an electrolytic condenser embodying the in vention of m prior Patent No. 1,077,627, issued November 4, 1913.

Fig. 3 is a diagrammatic plan view, partly in horizontal section, illustrating one embodiment of my present invention.

Fig. 4 is a diagrammatic plan view illus trating an embodiment of the present invention in which crimped or corrugated electrodes are used, for example electrodes of the type shown in my Patent No. 1,326,134, issued December 23, 1919.

Fig. 4 is a similar View preferred embodiment.

Fig. 5 is a. fragmentary perspective view of one of the electrodes shown in Fig. 4. F igs. 6, 7 and 8 illustrate other embodlbut showing the jments of the invention.

Fig. 9 is a central cross-section of Fig. 3, showing the inner insulating frame 1mmersed in the electrolyte and supported above the bottom of the outer vessel.

In Fig. 1 the path of the alternating current from plate 1 to plate 2, from 2 to 3, and from 3 to 4. is indicated by the straight double-headed arrows. In each case the path is relatively short, its length being merely the distance from one plate to the next. In the case of the end plates, however, the current from the outer surface of oneto the outer surface of the other must Serial No. 335,380.

take a much longer path, as indicated by the curved arrows, thereby encountering greater resistance and suffering greater heat losses. This disadvantage is eliminated by the scheme described in my prior patent above mentioned, in which collecting electrodes 5, 6, Fig. 2, are provided. Here the current from the outer surfaces of the end plates 1, 2, flows to the adjacent collecting electrodes and thence through the conductor 7. The resistance of the path is thus reduced to a negligible amount. The scheme described is in every way successful, but practically the only material available for collecting electrodes is carbon, and considerable diiiiculty has been experienced in obtaining carbon of the desired purity, thus making it necessary to subject the carbon plates or electrodes to a more or less troublesome process of purification to eliminate the impurities which would injuriously contaminate the electrolyte.

In my present invention I also employ additional electrodes, but I. make them active electrodes instead of merely collectors of current. At the same time they provide shorter paths for the currents from the outer surfaces of the end plates. This result is attained by making the additional electrodes of smaller active area than the adjacent end plates. Thus in Fig. 3, in which a simple embodiment of the invention is illustrated, the additional or special electrodes 8, 9, are approximately one-half the area of the end-plates 10, 11. The current paths are then as indicated by the arrows; Between plate 10 and electrodes 8, for example, the current path from and to the inner surface of 8 and the portion of the adjacent surface which 8 overlies, is directly from one to the other, as indicated by the straigl1t.double-headed arrows, while between the outer surface of 8 and the part or parts of 10 which extend beyond 8, the path is indicated by the curved arrows. So also betweeh plate 11 and electrode 9. Thus without more space than is required for the collecting electrodes 5, 6, Fig. 2, the necessity of current flowing through the electrolyte from and to plates 10 and 11 is avoided, and at the same time the active electrodearea is increased by the area of the two electrodes 8 and 9. Thus in Fig. 3, in which the area of plates 8 and 9 is about half the area of the adjacent plates 10 and 11 the Ill) result is equivalent to the addition of another whole electrode. 0f course it will be understood that the spacing of the plates in Fig. 3 is much exaggerated and that the arrows merely indicate the current paths in a very rough way, the figure being purely diagrammatic.

To aid in confining the current to the paths indicated by the curved arrows in Fig. 3 the entire set of plates may be enclosed in a box or frame 12, composed of glass or other suitable insulating material and. preferably close to but not incontact with the sideedges of the larger or full sized plates. By making the box open at the top I and bottom and supporting it above the bottom.- of the outer vessel it offers no material interference with the circulation of the electrolyte due to convection currents or other causes.

In practice I prefer to employ crimped plates or electrodes, say of the type illustrated in Figs. t and 5, and described more fully in my copending application hereinbefore mentioned. With such plates the smaller area of electrodes 8 and 9 may be obtained by making them with fewer crimps or corrugations, say only half as many, as in the others, though of about the same length and breadth. Thus in Fig. 4-, electrode 9 has half the number of corrugations that plate 11 has, and hence has substantially half the area. Another, and in most cases a better method, isto make the crimps or corrugations in the end electrodes of less depth, say about half. in general the numher or depth, or both, of the corrugations or crimps are made such as to give the desired lesser area. in Figs. l and 8, electrodes 8 and 9' have the same number of crimps as 10- and 11 have but they are shallower, being only half as deep. Preferably, also, the crimped plates, especially those of the smaller area, have openings or perforations, for example in the bends of the crimps as indicated at 13, Fig. 5, so that the current from the outer surfaces of plates 10 and ll can find electrolyte-paths, through these openings, to the outer surfaces of the plates 8 and 9*, as will be readily understood.

At 13, Fig. 3, is indicated an electrode composed of carbon or other material which is not subject'to chemical or electro-chemitill cal attack in the electrolyte, for the purpose of supplying exciting current to the condenser. The active electrodes 8, 10-1'1, 9, are connected in groups, those in each group being in multiple, as is customary. In the embodiments illustrated in Figs. 6, 7 and 8 an odd number of normal or full-size electrodes are used, one in Fig. 6 and three in Figs. 7 and 8. The end-plates 8, 9 14, 15, are of substantially half the area of the others, so that the result is practically the areal-ea equivalent of an even number of full-size plates, whereas if the end-plates were of full size one group would have a greater active area than the other and an unbalanced condition would obtain.

ln the appended claims the term Fseries is used to express the arrangement of the, electrodes side by side one after the other, and has no electrical significance.

It is to be understood that the invention is not limited to the specific constructions herein illustrated and described but can be embodied in other forms without departure from its spirit-as-defined by the following claims.

l claim:

1. ln an electrolytic condenser, an outer vessel Eontaining an electrolyte, an inner frame of insulating material immersed in the electrolyte, and a series of electrodes immersed in the electrolyte in said frame, all of which electrodes are active and of which the electrode at each end of the series is of lesser area than the next adjacent electrode, for the purpose set forth.

2. ln an electrolytic condenser, a series of active electrodes of appropriate area connected in groups, and active electrodes of lesser area located at the ends of the series and connected each to its appropriate group.

3. In an electrolytic condenser, a series of active electrodes of appropriate size composed of crimped or corrugated plates connected in groups, and active electrodes located at the ends of the series and connected to the appropriate groups, and having shallower crimps or corrugations than the adjacent electrodes of the series so as to have lesser active area.

4-. In an electrolytic condenser, a series of active electrodes of appropriate area composed of crimped or corrugated active electrodes of substantially the same dimensions as the others, but having shallower crimps or corrugations, located at the ends of the series and connected each to its appropriate group, the said electrodes having the shallower crimps or corrugations being provided with suitable apertures to provide unbroken current-paths of electrolyte between their outer surfaces and the adjacent plates of the aforesaid series.

5. In an electrolytic condenser, the apparatus described in claim 2, in combina 'tion with insulating means to aid in preventing fiow of current past the side edges of the electrodes'of greater area.

6. ln an electrolytic condenser, the apparatus described in claim 1, in combination with an enclosure of insulating material inside of the outer receptacle and enclosing the. electrodes to aid in preventing flow of current past the side edges of the electrodes of larger area.

of electrodes arranged side by side in the outer vessel and immersed in the electrolyte therein, and an enclosure composed of 1nsulating material and open at top and bottom, surrounding the plurality of electrodes and immersed in the electrolyte; to aid in preventing flow of current past the side edges of the electrodes.

In testimony .WhereOfI hereunto aflix my signature.

RALPH D. MER-SHON. 

